摘要:

AbstractThe new, fast, automatic focusing algorithms, namely Energy Maximization and Histogram Variance Maximization, for computer vision systems have been presented in this article. These two focusing algorithms have greatly reduced the arithmetical operations needed to perform an automatic focusing operation. Experimental evaluations and comparisons to previously developed algorithms have been performed and the results presented. The improved performance in accuracy and speed of our new algorithms will certainly benefit applications such as distance measurement, target tracking, and scene analysis by the use of computer vision techniques.

ISSN:0741-2223    

DOI:10.1002/rob.4620040402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractInverse Kinematics has been recognized as an important problem in robotics applications. A robot independent solution can only be obtained through numerical methods, but most solutions which use this approach have problems with convergence especially near singularity points. This article develops a strictly convergent algorithm and a special‐purpose Inverse Kinematics Processor (IKP) to obtain the solution in real time. While the algorithm is based on open‐loop integration of rates, the absolute position deviation is used as a criterion to control the iteration, and a feedback mechanism has been especially designed to eliminate problems with long‐term drift or with initial errors in the solution. The architecture of the IKP is based on a high‐speed floating‐point arithmetic processor and is designed to perform the common matrix‐vector operations efficiently with a minimum processor cycle time. The algorithm has been simulated on the proposed architecture, and the results show its robustness and real‐time capability. For a six degree‐of‐freedom robot manipulator (for which no closed‐form solution exist), the Inverse Kinematics solution may be obtained at an approximate 2 khz rate with an error which is within standard r

ISSN:0741-2223    

DOI:10.1002/rob.4620040403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractIn 1983 the authors implemented the computer program Algebraic Robot Modeler (ARM) to generate symbolically complete closed‐form and recursive dynamic robot models.1–3Then, in 1985, we incorporated in ARM heuristic rules for the systematic organization of dynamic robot models to reduce the computational requirements of customized forward and inverse dynamics calculations. We resolve the issue of numerical efficiency of customized closed‐form and recursive forward and inverse dynamics algorithms for kinematically and dynamically structured manipulators. We find that ARM‐generated customized closed‐form algorithms are the most computationally efficient calculators of forward and inverse dynamics of three degree‐of‐freedom manipulators. For six DOF predominantly rotational manipulators, ARM‐generated customized recursive algorithms are the most computationally efficient foward and inverse dynamics algorithms; inverse dynamics can be computed in less than one millisecond on commercially‐available processors (in software, without special‐purpose hardware). In our companion article,4we compare the symbolic efficiencies of six robot dynamics formulations for generating closed‐form

ISSN:0741-2223    

DOI:10.1002/rob.4620040404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractReal‐time robot control requires efficient inverse kinematics transformations to compute the temporal evolution of the joint coordinates from the motion of the end‐effector. The development of a coherent, general‐purpose framework, incorporating position, velocity and acceleration transformations, is the theme of this paper. In this framework, the computational requirements of a new inverse kinematic algorithm are delineated. The algorithm is applicable to serial (open‐chain) manipulators with arbitrary axes of motion. Comparative evaluations of the computational cost of the algorithm demonstrate its efficacy and feasibility for real‐time app

ISSN:0741-2223    

DOI:10.1002/rob.4620040405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThe article presents simple methods for the design of adaptive force and position controllers for robot manipulators within the hybrid control architecture. The force controller is composed of an adaptive PID feedback controller, an auxiliary signal, and a force feedforward term, and achieves tracking of desired force setpoints in the constraint directions. The position controller consists of adaptive feedback and feedforward controllers as well as an auxiliary signal, and accomplishes tracking of desired position trajectories in the free directions. The controllers are capable of compensating for dynamic cross‐couplings that exist between the position and force control loops in the hybrid control architecture. The adaptive controllers do not require knowledge of the complex dynamic model or parameter values of the manipulator or the environment. The proposed control schemes are computationally fast and suitable for implementation in online control with high sampling rates. The methods are applied to a two‐link manipulator for simultaneous force and position control. Simulation results confirm that the adaptive controllers perform remarkably well under different conditi

ISSN:0741-2223    

DOI:10.1002/rob.4620040406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

ISSN:0741-2223    

DOI:10.1002/rob.4620040401

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY